BitsPerSecond
Tricities, TN
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Well. I made the decision today. The brougham is on hold indefinitely. It's been a rough week. I've had a death in the family that I don't feel like discussing here. But I've got other things to deal with right now. I'll be disappearing from here for a while. I'll be back eventually.
Peace.
Chris
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Leeann
Maryland
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Joined: 08/22/2006
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We’ll be here. Take care of yourself and your family.
'73 Concord 20' Class A w/Dodge 440 - see profile for photo
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Ballenxj
Formerly Southern Nevada, Idaho now
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Joined: 02/03/2003
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BitsPerSecond wrote:Well. I made the decision today. The brougham is on hold indefinitely. It's been a rough week. I've had a death in the family that I don't feel like discussing here. But I've got other things to deal with right now. I'll be disappearing from here for a while. I'll be back eventually.
Peace.
Chris
Sorry to hear about your loss. ![[emoticon]](http://www.coastresorts.com/sharedcontent/cfb/images/frown.gif "frown")
You take care, and when you feel up to returning, we'll see you then. ![[emoticon]](http://www.coastresorts.com/sharedcontent/cfb/images/smile.gif "smile")
Downsizing ">
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StingrayL82
Nampa, Idaho
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BitsPerSecond wrote:Well. I made the decision today. The brougham is on hold indefinitely. It's been a rough week. I've had a death in the family that I don't feel like discussing here. But I've got other things to deal with right now. I'll be disappearing from here for a while. I'll be back eventually.
Peace.
Chris
You need to take care of yourself, Chris. The motorhome will always be there, your sanity not so much. I've had some issues, too. Though not a loss, an old wound opened wide, and I'm trying to stitch it back up.
* This post was
edited 08/29/18 09:29pm by StingrayL82 *
Fred
Retired Army Guy
2005 Monaco LaPalma 37PST
Workhorse W24 chassis
8.1L Vortec
Allison 2100 MH
Onyx Color Scheme
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BitsPerSecond
Tricities, TN
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Joined: 05/27/2018
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StingrayL82 wrote:
You need to take care of yourself, Chris. The motorhome will always be there, your sanity not so much. I've had some issues, too. Though not a loss, an old wound opened wide, and I'm trying to stitch it back up.
Yeah...I lost my partner of six years, out of nowhere. He was way too young. It's been rough, and I'm taking it a day at a time...He was fixing up his grandfather's sailboat for a trip we had planned for fall 2019. I decided to work on that instead...once I feel working again.
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Leeann
Maryland
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BitsPerSecond wrote:
Yeah...I lost my partner of six years, out of nowhere. He was way too young. It's been rough, and I'm taking it a day at a time...He was fixing up his grandfather's sailboat for a trip we had planned for fall 2019. I decided to work on that instead...once I feel working again.
****. I'm really sorry. I wish there was something I or anyone could do.
That just plain sucks.
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DRTDEVL
SPAM Town, USA
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Joined: 04/23/2014
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On a lighter note:
Here's a good question. On my 20RG (360 with Thermoquad), I am installing hitch and beefing up the frame extensions in order to flat-tow a 1988 Mitsubishi Montero (3100 lbs). We are moving in the spring... I was doing everything this winter to prepare for the cross-country trip, and my thoughts went to EFI. I found a self-learning aftermarket throttle body injection unit that replaces a 4-bbl and is good up to 400 hp. My Thermoquad always wants to run rich (I live at 4,000 feet now), but I don't want to re-jet it, only to have it too lean at sea level. This makes for poor fuel economy and difficult hot starting (need at least half pedal and a long crank to get enough air in to fire off).
Anyway, I get between 7-8 mpg now. I assume this will drop to 5-6 when flat-towing the Montero. I already had a custom exhaust put on to open up the flow (a single 2.25" pipe isn't enough for the 360 to breathe effectively, so its now 3"... but I haven't made any trips on the new exhaust to test out the potential fuel economy improvement). Is it reasonable to think that with the exhaust work and the fuel injection unit installed that I could break 10 mpg at 60 mph, and get 7-8 towing? My tires are already about 15% taller than factory, so the RPMs are a little lower going down the highway.
The plan:
Replace Thermoquad with EFI unit.
Add electric inline pump by tank for a more reliable fuel supply.
Replace coil with aftermarket, high output 12v unit.
Bypass ballast resistor.
Do basic maintenance before leaving: new bets and hoses again, new water pump.
The injection:
https://fitechefi.com/products/30003/
The pump:
https://www.holley.com/products/fuel_systems/fuel_pumps_regulators_and_filters/fuel_pumps/carbureted_fuel_pumps/carbureted_electric_fuel_pumps/parts/12-426
The Coil:
https://www.amazon.com/ACCEL-ACC-8140-Performance-SuperStock/dp/B00064P99W/ref=sr_1_10?s=automotive&ie=UTF8&qid=1544904461&sr=1-10&keywords=accel+super+coil
Resurrecting an inherited 1980 Minnie Winnie 20RG from the dead after sitting since 1998..
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Griff in Fairbanks
AK
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DRTDEVL -- My first (and invariable) caution is "bigger isn't always better." Also, remember you're driving a big truck so don't expect sports car acceleration. (Driving style has the single biggest effect on fuel economy ... moderate acceleration and minimal braking will improve economy.)
Exhaust back pressure is important so there's a fine line between too small and too big. 3 inch is not too big of a jump from 2.25 inch, especially for a heavily laden truck. (The same OEM exhaust is used across the range of 1/2- to 1-ton and vehicle use.)
OEM exhaust has to span the range from lightly to heavily laden, while keeping economy in mind. (Fuel and manufacturing economy.) Back in the mid-70's the general population started driving light trucks without frequent loads so manufacturers were able to go to smaller exhaust ... mostly to cut manufacturing cost.
Dual or single exhaust? If dual, X- or H-pipe crossover? You've already redone your exhaust so it's not worth revising. For others considering an exhaust change, dual (with X- or H-pipe crossover) is always better, if you can manage the additional cost of more pipe and more work.
EFI will be a significant improvement (all around) over fixed-jet carburetors. In addition to better fuel economy, it will solve the too rich/too lean issue.
Multi-port injection is better than single-port but costs significantly more. The biggest improvement is from fixed-jet to EFI and the improvement of multi-port versus single-port is minimal in comparison. (If you can afford it, there are multi-port injection intake manifolds available ... Edelbrock makes one for LA small blocks as well as other companies.)
Next step is to advance your timing a few degrees. A more complete burn leads to better use of available fuel and improved economy.
Your driving style will determine how much to advance the timing. You want the timing to be just short of pinging/knocking. If you're a 'lead foot' driver, you're probably better leaving the timing on stock specifications. If you are (or can change to) a less throttle type of person, you can get 1-4 mpg improvement by advancing timing. (Again, stock specifications cover the range from light- to heavy-throttle use.)
Changing from mechanical to electric fuel pump (in or near the tank) will solve other problems but won't affect fuel economy. (Unless you have other problems, such as leaky, old, too small, or substandard fuel lines.)
Be careful to not go overboard on the electric fuel pump. High volume/low pressure is best. Too much pressure will lead to other problems, including flooding or fuel system leaks. Your EFI instructions should specify appropriate fuel pressure (at the metering unit). If not, contact the manufacturer.
Think about fuel pressure as like taking a drink from a water hose. Reasonably easy from a low pressure (30-60 psi) garden hose. Difficult to impossible from a high pressure water line. (Along the same lines, that why there's regulators on breathing apparatus.)
Do NOT bypass the ballast resistor! At a minimum, you'll wind up wearing out plugs, cap, and rotor much, much quicker. You could very well burn up ignition system components, such as coil and ignition module, due to constant higher voltage.
Ignition system components (obviously) can withstand brief periods of higher voltage. Constant higher voltage does not allow the components recovery (mostly heat dissipation) time.
Electronic ignition is especially sensitive to extended high voltage. Imagine replacing your computer's standard 6V power supply with a 12V unit or running a 120V light bulb on 180V.)
Advancing the timing will do what you're trying to do with hotter spark. (More complete fuel burn.) Hotter spark in an otherwise fully functional ignition system won't change fuel economy set to stock timing.
There's plenty of literature on the internet about how to 'read' spark plugs. Read and follow that before deciding you need a hotter spark or hotter plugs.
In general, black sooty deposits indicate a too-cold plug. Plugs that wear out quickly (assuming adequate quality control) indicates high ignition system voltage or the wrong plug. Difficulty starting and poor fuel economy are two indicators of plugs that are too hot. (Yes, you're going to need to drive your motorhome some to diagnose the ignition system via plugs.)
I strongly recommend staying with a stock ignition coil. I've never had to change coils unless one has gone bad. On the other hand, I have managed to tweak better fuel economy without changing coil, mostly by changing driving style and advancing timing. (4-6 mpg improvement is typical for me.)
The aftermarket coil you mentioned is intended for sports cars and high performance (race car) engines. For most people, it's a placebo -- serving primarily as a mildly expensive ego boost. (The latter includes your motorhome with a stock LA small block.)
1970 Explorer Class A on a 1969 Dodge M300 chassis with 318 cu. in. (split year)
1972 Executive Class A on a Dodge M375 chassis with 413 cu. in.
1973 Explorer Class A on a Dodge RM350 (R4) chassis with 318 engine & tranny from 1970 Explorer Class A
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DRTDEVL
SPAM Town, USA
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The exhaust is single. I wanted to go with 2.25" duals, but there simply wasn't enough room to properly route the passenger side pipe. The difference was noticeable on the drive home. With the single 2.25", I could hear an audible hissing from the exhaust under load, like climbing over San Augustine Pass by my house or when accelerating onto the interstate highway. I had the exhaust lengthened at the same time to exit all the way at the rear corner of the body, rather than behind the tire, to stop the gases from getting in the rear side sliding window, as they were doing with the stock exhaust.
My driving style? I have driven for a living for most of my adult life. Fuel economy is premium to me, and that's probably how I managed 8.4 mpg on my last trip in the RV in the mountains.
The idea of the 12v coil was for simplicity. One less thing to potentially fail on the highway. It's not a hotter spark idea, rather a "I don't want to be caught changing the ballast resistor on the side of US 54 outside of Liberal, Kansas" kind of thing.
I can read the plugs, and they show a rich condition. Not bad enough to foul them out, but enough to remind me that I am jetted for sea level yet primarily operating at 4000-11000 feet. This is changing in May, however, as where we are moving is only around 1,000 feet.
Further research shows that the fuel pump I was going to use does not supply enough pressure. The EFI unit needs 58 psi to properly operate. I am now looking at a different Holley unit, capable of 80 psi. The EFI has a built in pressure regulator for 58 psi, and I just need to run a return line to the factory return line by the original fuel pump.
(BTW: All backpressure is bad. Its a misnomer. All that is required is proper scavenging of the gases. This is commonly misidentified as a backpressure requirement.)
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Griff in Fairbanks
AK
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DRTDEVL wrote:BTW: All backpressure is bad. Its a misnomer. All that is required is proper scavenging of the gases. This is commonly misidentified as a backpressure requirement.
My bad ... I used an outdated term. You are very correct, proper exhaust scavenging is vital for performance and efficiency.
30-40 or more years ago, 'back pressure' was the term used when 'scavenging' was more appropriate and what should have been used all along. My understanding of exhaust dynamics should have made me realize, decades ago, that I was using a misleading and inappropriate term. Thank you for correct my vocabulary.
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